public class RoundImageView extends ImageView {
public static final int TYPE_CIRCLE = 0;
public static final int TYPE_ROUND = 1;
/**图片的类型，圆形or圆角，值请参考TYPE_CIRCLE或TYPE_ROUND*/
private int viewType;
/**圆角的大小*/
private int roundRadiu;
/**圆形的半径*/
private int circleRadiu;
/**记录圆角矩形的边界*/
private RectF mRoundRect;
private Paint mBitmapPaint;
public RoundImageView(Context context) {
this(context, null);
}
public RoundImageView(Context context, AttributeSet attrs) {
super(context, attrs);
mBitmapPaint = new Paint();
mBitmapPaint.setAntiAlias(true);
TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.RoundImageView);
roundRadiu = typedArray.getDimensionPixelSize(R.styleable.RoundImageView_borderRadius, dp2px(10));//默认为10dp
viewType = typedArray.getInt(R.styleable.RoundImageView_type, TYPE_CIRCLE);//默认为圆形
//circleRadiu的大小需要在onMeasure根据测量到的宽高确定
typedArray.recycle();
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
//因为我们是直接继承ImageView(而不是继承自View)，所以直接调用super方法就能正确得到实际的宽高(按ImageView默认的规则)
if (viewType == TYPE_CIRCLE) {
int mSize = Math.min(getMeasuredWidth(), getMeasuredHeight());
circleRadiu = mSize / 2;
setMeasuredDimension(mSize, mSize);//实际的大小
}
}
@SuppressLint("DrawAllocation")
@Override
protected void onDraw(Canvas canvas) {
Drawable drawable = getDrawable();
if (drawable == null) return;
//1、根据Bitmap要裁剪的类型，以及bitmap和view的宽高，计算Bitmap需要缩放的比例
Bitmap bitmap = drawableToBitamp(drawable);
float scale = calculateBitmapScale(bitmap);
//2、为BitmapShader定义一个变换矩阵Matrix，通过Matrix对Bitmap进行缩放
Matrix mMatrix = new Matrix();
mMatrix.setScale(scale, scale);
//3、通过Matrix将缩放后的Bitmap移动到View的中心位置
float dx = getMeasuredWidth() - bitmap.getWidth() * scale;
float dy = getMeasuredHeight() - bitmap.getHeight() * scale;
mMatrix.postTranslate(dx / 2, dy / 2);//注意只能用一个set方法，其他的要用post或pre方法
//4、通过BitmapShader对Bitmap进行渲染，
BitmapShader bitmapShader = new BitmapShader(bitmap, TileMode.MIRROR, TileMode.REPEAT);//后两个参数：填充模式
bitmapShader.setLocalMatrix(mMatrix);//由于我们已经让Bitmap的宽高一定【大于】view的宽高，所以上面的填充模式是没有任何效果的。
mBitmapPaint.setShader(bitmapShader);
//5、最后画出所需要的图形
if (viewType == TYPE_ROUND) {
// 【一】可以在这里通过getWidth、getHeight获取View的大小
mRoundRect = new RectF(0, 0, getWidth(), getHeight());
canvas.drawRoundRect(mRoundRect, roundRadiu, roundRadiu, mBitmapPaint);//在哪个矩形区域绘制，圆角大小
} else {
canvas.drawCircle(circleRadiu, circleRadiu, circleRadiu, mBitmapPaint);//圆心坐标，半径
}
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
// 【二】也可以在这里直接使用系统帮我们测量的准确的View的大小
// if (viewType == TYPE_ROUND) mRoundRect = new RectF(0, 0, w, h);
Log.i("bqt", "w=" + w + "--h=" + h);
}
/**drawable转bitmap*/
private Bitmap drawableToBitamp(Drawable drawable) {
if (drawable instanceof BitmapDrawable) {
BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable;
return bitmapDrawable.getBitmap();
}
int drawableWidth = drawable.getIntrinsicWidth();
int drawableHeight = drawable.getIntrinsicHeight();
Bitmap bitmap = Bitmap.createBitmap(drawableWidth, drawableHeight, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
drawable.setBounds(0, 0, drawableWidth, drawableHeight);
drawable.draw(canvas);
return bitmap;
}
/**计算Bitmap需要缩放的比例*/
private float calculateBitmapScale(Bitmap bitmap) {
float scale = 1.0f;
if (viewType == TYPE_CIRCLE) {
int bSize = Math.min(bitmap.getWidth(), bitmap.getHeight());
scale = circleRadiu * 2.0f / bSize;
} else if (viewType == TYPE_ROUND) {
// 如果Bitmap的宽或者高与view的宽高不匹配，计算出需要缩放的比例；缩放后的Bitmap的宽高，一定要【大于】view的宽高
if (bitmap.getWidth() != getWidth() || bitmap.getHeight() != getHeight()) {
float scaleWidth = getWidth() * 1.0f / bitmap.getWidth();
float scaleHeight = getHeight() * 1.0f / bitmap.getHeight();
scale = Math.max(scaleWidth, scaleHeight);
}
}
Log.i("bqt", "缩放比例" + scale);
return scale;
}
/**根据屏幕规格，将dp值转为px值*/
public int dp2px(int dpVal) {
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dpVal, getResources().getDisplayMetrics());
}
//对外公布两个方法，用于动态修改圆角大小和type
public void setBorderRadius(int borderRadius) {
int pxVal = dp2px(borderRadius);
if (roundRadiu != pxVal) {
roundRadiu = pxVal;
invalidate();
}
}
public void setType(int type) {
if (type != TYPE_ROUND && type != TYPE_CIRCLE) {
type = TYPE_CIRCLE;
}
if (viewType != type) {
viewType = type;
requestLayout();
}
}
}